Review copy provided by Tor Books. Also the author is a personal friend.

What do I want in the middle book of a trilogy? Well. I want consequences from the first book. If the events of the first book are unimportant, it’s not so much a trilogy as a set of standalones. I want further developments of the characters. If they are exactly who they are at the beginning of the first book when the beginning of the second book rolls around, that undermines the importance of the events of the first book. And I want more worldbuilding. Whatever made the first book cool, there should be more of it. I like even stand-alone books to give me a sense that there’s more there there than will fit in one book; I want that sense to expand with the middle book in a series. Nuance, complication, detail.

Cloudbound does all of that. The point of view character changes from Kirit to Nat, which gives some obvious ways to handle everything good in a sequel: Nat’s thoughts and opinions and knowledge are not Kirit’s. His priorities are not Kirit’s. His skills are not Kirit’s. So there is an entirely different angle on the towers, the Spire, the Singers, and the culture at hand–in addition to the new events unfolding before us. Science! Treachery! Exploration! Protective interpersonal relationships! There’s plenty to sink your teeth into in this book.

Because it is so thoroughly the middle book of a trilogy, I would recommend starting with Updraft. But that’s readily available in new formats now, so there’s really no reason not to. The worldbuilding will be clearer if you’ve read the first book, but more importantly, the emotional impact will be stronger. So go ahead and get started on that!